DI 23022.690 Cerebrotendinous Xanthomatosis

Cerebrotendinous Xanthomatosis (CTX) is an inherited lipid storage disorder where the body lacks the enzyme to break down different forms of cholesterol, leading to lipid accumulation in all tissues in the central nervous system, as well as in the tendons, skin, lungs, and bones. The disease is characterized by chronic diarrhea during infancy, cataracts developing in late childhood, progressively brittle bones that are prone to fracture, and neurological problems in adulthood, such as dementia, seizures, hallucinations, depression; and difficulty with coordinating movements (ataxia) and speech (dysarthria). Xanthomas (fatty yellow nodules) in the tendons begin to form in early adulthood. People with CTX are also at an increased risk of developing cardiovascular disease.

DIAGNOSTIC TESTING, PHYSICAL FINDINGS, AND ICD-9-CM CODING

Diagnostic testing: The diagnosis of CTX is established by a combination of clinical examination, molecular genetic testing for the CYP27A1 gene, and biochemical testing. Individuals with CTX have a high cholesterol concentration, normal-to-low plasma cholesterol concentration; decreased chenodeoxycholic acid; increased concentration of bile alcohols and their glyconjugates; and increased concentrations of cholestanol and apolipoprotein B in cerebrospinal fluid.

Cataracts develop in childhood or adolescence, and xanthoma formation tends to develop in the second and third decades of life. Neurological impairments involving seizures, dementia, and involuntary reflexes and movement begin in the third decade of life and progress until death. The severity of CTX varies widely with the cause of death usually due to myocardial infarction and progressive mental deterioration.

TREATMENT

There is no current cure for CTX. Treatment focuses on the management of disease symptoms. Cataract extraction is typically required in at least one eye by the age of 50 years. Seizures, spasticity, and parkinsonism are treated symptomatically.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for evaluation:

Clinical history and examination that describes the diagnostic features of the impairment and laboratory studies are needed to confirm the diagnosis.

Imaging studies such as an MRI or CT scan of the brain showing diffuse atrophy in the cerebellum, basal ganglia, and cerebrum.

Suggested Listings for Evaluation:

DETERMINATION

LISTING

REMARKS

Meets Listing

11.17

12.02

111.06

112.02

Medical Equals

* Adjudicators may, at their discretion, use the Medical Evidence of Record or Listings suggested to evaluate the claim. However, the decision to allow or deny the claim rests with the adjudicator.